Drafting apparatus of textile spinning machines



March 31, 1959 w, HUNTER 2,879,551

'DRAFTING APPARATUS OF TEXTILE SPINNING MACHINES Filed March 28, 1955 2 Sheets-Sheet 1 W. A. HUNTER March 31, 1959 I DRAFTING APPARATUS OF TEXTILE SPINNING MACHINES Filed March 28, 1955 2 Sheets-Sheet 2 ni i a 2,879,551 APPARATUS or TEXTILE SPINNING MACHINES William Aldred Hunter, Stanhill, Accrington, England,

assignor to T. M. M. (Research) Limited, Oldham, England 1 Application March 28, 1955, Serial No. 497,303 3 Claims. '(Cl. 19-157) invention is concerned with the means which ,are employed for condensing and consolidating a strand of fibres in its passage between drafting zones in the drafting apparatus of a textile spinning machine. It is customary in most multi-zone drafting apparatuses to consolidate the strand, for example in a neutral zone between two main drafting fields, with the object of counter-acting the aberration or disarrangement which occurs more particularly at the margins of the partially drafted strand by reason of the relative fibre movement in drafting, and which may result in considerable fibre loss.

The effect of the initial drafting operation in the first zone of a multi-zone drafting system is to orientate and to some extent parallelize the fibres in the direction of the axis of the strand, and it is important to main this condition during the passage of the strand through the following zone, in order that the strand may be presented at the next drafting stage in the compact and parallelized form in which it will, by virtue of the inter-fibre friction and the arrangement of the fibres, be best adapted to give the maximum regularity of fibre distribution in the finally attenuated form. The object of this invention is to provide a condenser for use in the circumstances referred to, which will effect the desired consolidation of the partially drafted strand.

A condenser for the drafting apparatus of a textile spinning machine, according to this invention, is nonrotating and is fashioned in such manner as to impart to the strand an arcuate cross-sectional formation, to preserve such formation throughout the effective length of the condenser, and to deliver the strand in that form. The cross-sectional area of the condenser passage may be diminished in the direction of the exit orifice so that, and the transverse cross-sectional shape of such passage may be such that, the condenser being mounted with the highest part of the lower surface of the passage above the shortest path of the fibres, the fibres are crowded towards the margins of the strand and thereby compressed so as to be held against lateral displacement in or detachment from the strand.

It is preferred that the arcuate formation of the strand cross-section shall be maintained in the same curvature during its passage through the condenser, and that the vertical interior dimension of the condenser, which determines the thickness of the strand, shall be substantially constant throughout its effective length, the diminution in the cross-sectional area of the condenser being due solely to the reduction of the length of the arcuate distance between its side-walls.

The invention also provides a method of processing a strand of textile fibres, consisting in subjecting the strand to an initial drafting operation, subsequently condensing the strand by imparting to it an arcuate cross-sectional formation whereby the fibres are crowded towards and compacted at the marginal edges of the strand without disturbance of their relative lateral disposition, and delivering the strand as it leaves the condensing stage in an arcuate cross-sectional form.

I 2,87 9,551 ea sillt an 3 1 .9

7 t'lhemannsr n whi h tbeinvc t os sto be P f m is .h r a rmere full sc i ed wit ref e t the accompanying drawinga in which Fig. 1 is an elevation of an improved condenser, showing'the entry orifice, Fig, 2 is a cross-section drawn-to a larger scale, and Fig. 3 is a plan. Fig, 4 is a diagrammatic sectional view of the dual zone drafting apparatus of a textile s eed frame incorporating four lines ,of drafting rollers, in which thecondenser illustrated in Figs. 1 to 3 is installed in the neutral zone between the second and third lines of rollers, the condenser being shown in section as taken on the n X -Y of 'Fig- Fi 5 s fr gm n a y perspective view deplctingthe action of the condenser on the strand. I I I a t-Wi lie e tram :F s .H S hat hs c n en there shown is fashioned as a small one-piece moulding, pressing or stamping of plastic or other appropriate material, being provided with an upright column A by which the condenser may be mounted upon a traverse bar or other suitable support. The body B of the condenser, which is carried at the top of said column, is shaped so as to provide a passage or guide for the strand of fibres in their path through the neutral drafting zone. The basal-surface C of the part forming said passage is made of convex cross-sectional formation, and the upper surface D of said passage is made concave so that its cross-section is parallel to that of the convex basal surface. The passage is rounded at either side at E, and a body of fibres traversing the condenser assumes an arcuate cross-sectional shape.

The transverse dimension of the condenser is progressively lessened in the direction of the exit orifice F.

In use, the condenser is mounted in the neutral zone between the second pair of rollers 10,- 11 of the first drafting zone and the first pair of rollers 12, 13 of the second drafting zone in a position in which substantially throughout the effective length of the condenser the central line of the floor or foot-wall of its passage is slightly above the plane containing the nips of the roller pairs 10, 11 and 12, 13 and the effect is to induce the fibres to disperse laterally towards the marginal parts E, in such manner as to compress the strand at its edges. Not only does the device prevent disarrangement or interference with the flanking fibres as they enter the condenser, but it ensures their retention relative to the other fibres in the body of the strand of the position which they have assumed in their passage through the initial drafting zone.

In order to avoid any tendency for folding or crimping of the fibres as they enter the condenser, it is preferably provided with a bell-mouthed lead-in orifice, as shown at K (Figs. 1 and 4).

The condensed strand is presented to the rollers 12, 13 of the second drafting zone with its fibres occupying substantially the positions which they occupied on leaving the rollers 10, 11 of the first zone, and since it is possible to set the exit orifice F of the condenser very close to the nip of the rollers 12, 13, the consolidated arrange ment of the fibres is preserved by the control which is immediately exercised by said rollers.

To facilitate the initial threading of the strand through the condenser the upper part of the body of the latter may be slotted lengthwise as at J.

In referring to the cross-sectional shape of the passage through the body B of the condenser as arcuate or as having the form of an are, it is not intended that the passage be necessarily limited to a circular configuration. The passage may take various forms of curvature, but is continuously upwardly convex. It is desirable that the passage shall be symmetrically formed with respect to vertical, central plane. It is essential that the angular extent of the passage be less than two right angles, i.e., that tangents drawn at the right-hand and left-hand ex 3 trcmities of the passage intersect in a point located above an intermediate portion of the passage.

What I claim as my invention and desire to secure by Letters Patent is:

1. In or for the drafting apparatus of a textile spinning machine, a non-rotating condenser providing a through passage the cross-sectional form of which is an arc having an angular extent of substantially less than two right angles, and having throughout its length spaced strandunderlying and -overlying surfaces of respectively convex and concave shape, such that, the strand-underlying surface being located with its highest point above the shortest path of the fibres, the fibres are laterally dispersed so as to be crowded and compacted without folding at the margins of the strand, and an exit orifice preserving the cross-sectional arcuate form of the strand and holding the latter against folding under the influence of the drafting elements of a subsequent zone.

2. A condenser as claimed in claim 1 wherein the v 4 strand-underlying and strand-overlying surfaces are parallel and of constant curvature between entry and exit 3. A condenser as claimed in claim 2, wherein the interior vertical dimension of the passage is substantially constant throughout its efiective length.

References Cited in the file of this patent UNITED STATES PATENTS 2,187,830 Jones Ian. 23, 1940 2,335,108 Clapperton Nov. 23, 1943 2,611,155 Cravens Sept. 23, 1952 2,755,514 Noguera July 24, 1956 FOREIGN PATENTS I 632,266 Great Britain Nov. 18, 1949 725,999 Germany Oct. 3, 1942 971,010 France June 28, 1950 

